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Clifton B.
Clifton B., ASE Master Auto Tech
Category: Nissan
Satisfied Customers: 4004
Experience:  ASE Master Certified Tech, Nissan Master Certified Tech, 12 yrs. experience in auto repair.
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I have a 1996 Nissan Altima that is running rich. I went to

Resolved Question:

I have a 1996 Nissan Altima that is running rich. I went to Autozone and got a basic engine light readout as my check engine light recently came on. It said that there was a possible egr valve blockage and also a possible O2 sensor problem. After looking at reviews online I read that these problems are ususlly from a faulty O2 sensor. I was wondering if this was true, and if it is, would it be the O2 sensor before or after the catalytic converter?
Submitted: 8 years ago.
Category: Nissan
Expert:  Clifton B. replied 8 years ago.
hi i will need the code they got from the car at autozone
Customer: replied 8 years ago.
<p>The first code was P0400</p><p> </p><p>This was about the egr valve - said it deteced too little airflow in the egr system.</p><p> </p><p>The second code was P0136</p><p> </p><p>this was for the O2 sensor </p>
Expert:  Clifton B. replied 8 years ago.
ok the po136 is for the rear o2 sensor that is the one under the car in the middel of the body replace it,,,,,,1/2
Classification: Reference: Date:
EC98-022 NTB98-084 October 15, 1998
APPLIED VEHICLE(S): All 1995-97 Altima
Use this bulletin if a 1995-97 Altima will not maintain idle or idles roughly and/or the MIL is
"on" with DTC P0400 stored in the ECM.
A new EGR valve is available to resolve such incidents if the cause is a sticking EGR valve.
Perform an inspection of the EGR valve as follows:
1. Slowly apply vacuum to the EGR valve with a hand vacuum pump, then release the
vacuum (see Figure 1).Check to see that the EGR valve opens when the vacuum is slowly applied and closes
when the vacuum is released.
A. If the EGR valve sticks open or does not open and close smoothly, replace the EGR
valve with the EGR valve and gasket listed below.
B. If the EGR valve opens and closes smoothly, use ASIST or refer to Trouble
Diagnosis in the EC section of the appropriate service manual to diagnose this
EGR valve 14710-4E801 1
EGR valve gasket 14719-W0402 1
if you have more question please ask
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